CVE-2017-18446 in cPanel
Summary
by MITRE
cPanel before 64.0.21 allows file-read and file-write operations for demo accounts via the SourceIPCheck API (SEC-250).
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Analysis
by VulDB Data Team • 07/19/2020
The vulnerability identified as CVE-2017-18446 represents a critical security flaw in cPanel versions prior to 64.0.21 that affects the SourceIPCheck API functionality. This issue enables unauthorized file read and write operations through demo accounts, creating a significant access control bypass that undermines the security model of the hosting control panel. The vulnerability specifically targets the API endpoint responsible for checking source IP addresses, which was improperly configured to allow demo user accounts to perform operations typically restricted to authenticated administrators. This flaw demonstrates a fundamental failure in the principle of least privilege implementation within the cPanel security architecture.
The technical exploitation of this vulnerability occurs through the SourceIPCheck API endpoint which fails to properly validate user permissions for demo accounts. When demo users interact with this API, they can leverage the insufficient access controls to execute file read and write operations on the system. The vulnerability stems from inadequate input validation and authorization checks that should have been implemented to prevent demo accounts from accessing core system functions. This issue aligns with CWE-284, which addresses improper access control vulnerabilities, and specifically manifests as a lack of proper authentication and authorization mechanisms. The flaw allows attackers to potentially access sensitive files, modify system configurations, or inject malicious content into the hosting environment through the compromised demo account.
The operational impact of this vulnerability extends beyond simple privilege escalation, as it creates opportunities for persistent access and data exfiltration within compromised cPanel environments. Attackers could leverage this vulnerability to gain unauthorized access to customer data, modify website content, or establish backdoors for continued access. The implications are particularly severe in shared hosting environments where multiple customers share the same infrastructure, as a single compromised demo account could potentially affect numerous websites and user accounts. This vulnerability directly impacts the security posture of web hosting providers and their customers, potentially leading to data breaches, website defacement, or unauthorized service modifications. The attack vector is particularly concerning as it does not require elevated privileges or complex exploitation techniques, making it accessible to threat actors with basic knowledge of the system architecture.
Organizations should immediately implement the available patch for cPanel version 64.0.21 or later, which addresses the improper access control in the SourceIPCheck API endpoint. Security administrators should conduct comprehensive audits of all demo accounts to ensure no unauthorized access has occurred, while also implementing additional monitoring for suspicious API activity related to file operations. The remediation process should include reviewing and strengthening access control policies for all user accounts, particularly those with limited privileges. Organizations should also consider implementing network segmentation and additional API rate limiting measures to prevent abuse of vulnerable endpoints. This vulnerability highlights the importance of regular security updates and proper access control implementation, aligning with ATT&CK techniques related to privilege escalation and credential access. The incident serves as a reminder of the critical importance of maintaining up-to-date security patches and the potential consequences of inadequate access control mechanisms in web hosting platforms.